Cold Crash Question

[bracconiere]

I'm using a glycol chiller with a coil...

sounds like a nice system!

 

[dan46nbrew]

well, cool, report back how much psi it loses in the fridge! (for my educational purposes)

Can't get it any lower than 40F, its lost about 2.5PSI... it was fermenting at 58F

 

[bracconiere]

Can't get it any lower than 40F, its lost about 2.5PSI... it was fermenting at 58F

appreciate the update !

 

[Pablo 54]

You all just made me nervous about my process. I use a FermZilla All Rounder. When I cold crash, the sides collapse in but, in my mind, as long as the collar does not flex, I'm good to go.
When I transfer to the keg, I gently pressurize the All Rounder. The sides flex back, with a little bit of the trub going back into suspension when the sides "pop" back to their original position.
Now I'm wondering if the All Rounder has a finite number of times it can flex before it splits and explodes in my fermentation chamber.
If I understand correctly, once I take off the blowoff tube, I should pressurize the All Rounder to 5 PSI before cold crashing.

 

[eric19312]

I ferment in a freezer. I usually will start cold crash at about 10 PSI in the headspace and check on it a few times a day as temp drops. Top up the head space as it starts to fall. For some beers I cold crash below 30F with freezer temp set to not get colder than 20F. I'll need to top up CO2 in headspace multiple times on one of those crashes.

 

[Pablo 54]

I'm about a three or four days away from my FG. I like the 10PSI. I may pull the blowoff tube now and see how much CO2 I can naturally develop before pumping in anything.

Thanks for the advice.

 

[k-daddy]

You all just made me nervous about my process. I use a FermZilla All Rounder. When I cold crash, the sides collapse in but, in my mind, as long as the collar does not flex, I'm good to go.
When I transfer to the keg, I gently pressurize the All Rounder. The sides flex back, with a little bit of the trub going back into suspension when the sides "pop" back to their original position.
Now I'm wondering if the All Rounder has a finite number of times it can flex before it splits and explodes in my fermentation chamber.
If I understand correctly, once I take off the blowoff tube, I should pressurize the All Rounder to 5 PSI before cold crashing.

5 psi may not be enough to counter the “shrinkage” when chilling the beer. I’m not sure what the pressure limits are for the all rounder but I would pressurize higher just to be safe or check occasionally throughout the crash to make sure you’re in positive territory and add pressure if needed.

 

[Pablo 54]

Agreed. I think I'll go with the 10PSI suggested by eric19312. I disconnected the blow off tube. I'll check my pressure tomorrow and see where I'm at. I still have a few points to go.

 

[Bobby_M]

i thought of that too, if people have to worry about putting a conical that costs $1k in the fridge, maybe a design improvement for them?

No need. You just spend 10% more for a co2 tank and regulator since it has so many other uses anyway. There is little need to improve the vacuum potential.

 

[Bobby_M]

.(and i just thought about canning, why don't all the mason jars implode?)

The ability of a cylinder to withstand vacuum is related to the strength of the material and the radius. Mason jars have a pretty thick wall and small radius. On a larger tank, the material is pretty strong but the radius is is larger so it's more susceptible to buckling. In other words, the cross section is less of a dome, and more flat (relative to a mason jar).

 

[bracconiere]

The ability of a cylinder to withstand vacuum is related to the strength of the material and the radius. Mason jars have a pretty thick wall and small radius. On a larger tank, the material is pretty strong but the radius is is larger so it's more susceptible to buckling. In other words, the cross section is less of a dome, and more flat (relative to a mason jar).

well, like i said...this is something i have to see to believe. the only way this thing would buckel from a vacuum i can imagine, which might actually do it....is if i used it as a pressure cooker, didn't realse the pressure. sealed it up THEN put it in the fridge.....but like i said, i laid it on it's side and stood on it with both feet, didn't even flex...so when ever my cider, that i added cranberry cocktail to decides to actually finish fermenting, i plan to pull the vacuum guage off my hand held pump....stick it in my blow off tube and see what i get...but i strongly doubt it will be a imploded milk can, although that would be COOL/COLD! (my head would start swimming with awesome science projects to try!)

 

[DarrellQ]

5 psi may not be enough to counter the “shrinkage” when chilling the beer. I’m not sure what the pressure limits are for the all rounder but I would pressurize higher just to be safe or check occasionally throughout the crash to make sure you’re in positive territory and add pressure if needed.

I use a modified Fermonster and put 5 psi on it during cold crash. I have never had a problem with any collapsing. Although, once I forgot to turn on the CO2 and woke up in the middle of the night a remembered. Good thing, because it was down to 45 degrees and was collapsing like it was being squeezed by Aaron Donald.

 

[dan46nbrew]

Pressurizing to 5PSI worked out fine, was able to get down to 38F cold crashing and still had 2 PSI left... it took a few more days because I had a power outage. Beer tastes great too!

 

[bracconiere]

just a quick update, i put my 16 gallon ferment with 10 gallons of cider in the fridge while it was still 80f, sealed it up....got it down to 40f over night....


i sealed it up with my vacuum pump to hopefully see how it built up....was disapointed it didn't implode as warned...so i thought damn gotta try this again...


but damn it was a struggle to get the lid of this milk pail, and it was sure sealed up tight...probably be a good way to save wort for later use!

like a little SS 1 gallon milk can, just dump the boiling hot wort in and put the lid on....for starters and such?

 

[eric19312]

Im sorry you failed to implode your fermentor! did you have a camera set up to capture the event just in case?

Anyway I'm less worried about the catastrophic collapse shown previously and more concerned that the seal may fail and let in some air. I assume the tri clover gaskets are probably tight in both directions but I'm not as confident in the giant band clamp gasket.

Anyway thread is good reminder it is time to start soft crashing my IPA.